Exemplary embodiments of the inventive concept relate to a complementary metal-oxide-semiconductor (CMOS) image sensor, and in particular, to CMOS image sensors with improved optical characteristics.
An image sensor is a device that converts optical images into electrical signals. With increased development of the computer and communications industries, there is an increased demand for high performance image sensors in a variety of applications such as digital cameras, camcorders, personal communication systems, gaming machines, security cameras, micro-cameras for medical applications, and/or robots.
The image sensors may be generally classified into charge coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) image sensors. The CMOS image sensors are operated using a simple operation method and are configured to have signal processing circuits integrated on a single chip, and thus, CMOS image sensors make it possible to realize products including scaled CMOS image sensors. In addition, CMOS image sensors may operate with relatively low consumption power, and thus, they are applicable to portable electronic devices. Furthermore, CMOS image sensors can be fabricated using cost-effective CMOS fabrication techniques and can provide high resolution images. Accordingly, the use of CMOS image sensors has increased.